The present invention relates to railway track assemblies and more particularly to an apparatus and method for embedding railway tracks at crossing sites.
Railway track assemblies typically employ a pair of steel rails supported by a plurality of perpendicularly disposed ties that rest on a ballast material. Where roadways intersect or coincide with railway tracks, it is necessary for non-rail vehicles to cross over the railway track assemblies. Often it is desirous to embed the railway tracks so that the top surface of the rails is substantially the same height as the finish grade of the surrounding surface. Embedding the rails in the surrounding surface allows the non-rail vehicles to pass over the rails without discomfort to the non-rail vehicle occupants, damage to the non-rail vehicles, or damage to the track structure.
Each pair of rails forming a track have inner sides which are called xe2x80x9cgaugexe2x80x9d sides. The xe2x80x9cgaugexe2x80x9d sides face each other. The outer sides of the pair of rails forming a track are called xe2x80x9cfieldxe2x80x9d sides. The rails may be embedded in a surrounding surface on the xe2x80x9cgaugexe2x80x9d side and the xe2x80x9cfieldxe2x80x9d side. One of the more common surrounding surfaces is a concrete panel. When rails are embedded in a surrounding surface such as concrete panels, gaps must exist between the rail and the surrounding surface. The gaps between the rails and the surrounding surface or panels allow the wheels of the rail-guided vehicle to pass without obstruction and prevent the surrounding surface from contacting and moving the rails into an unusable out-of-alignment position.
The gap between the rail and the surrounding surface causes problems such as the accumulation and flow of fluids and foreign objects between the rail and the surrounding surface. These fluids and foreign objects can damage railway crossing system components, such as ballast, ties, and the attaching hardware. Another problem is that when the surrounding surface is moveable, the gap can allow the surrounding surface or panel to contact or move too close to the rails. In particular, when the center panels of the embedded railway track assemblies are not fixedly attached to the railway ties, the center panels can contact or move too close to the rails.
The gap between the rail and the surrounding surface or panels may be filled with material such as asphalt, timber, or an elastomeric material such as natural or synthetic rubber. Such fillers may be attached or not attached to the surrounding surface or panel. One problem with such fillers is that they can be difficult to install, remove, reinstall or replace during, for example, track and ballast inspection and maintenance. A problem with unattached fillers is that they can shift rotationally, laterally, or longitudinally out of their correct installation position during use. A particular problem with existing attached fillers is that they can not be removed, reinstalled or replaced without also moving or removing the surrounding surface or panel. Another problem with attached fillers is that it may be necessary to replace the surrounding surface or panel when the attached filler is replaced.
The passage of non-rail vehicles over the embedded railway track assemblies and the exposure to the elements and caustic fluids and foreign objects causes a deteriorating effect on the embedded railway track assemblies. It therefore is desirable to construct the embedded railway track assemblies out of durable materials.
For the foregoing reasons, there is a need for durable embedded railway track systems that reduce the flow of fluids and other foreign objects between the rail and the surrounding surface, that prevent a moveable surrounding surface from contacting or moving too close to the rails, that are removably attached to the surrounding surface, and that are easy to install, remove, reinstall and replace without moving or removing the surrounding surface.
U.S. Pat. No. 5,850,970 to Hull (the present inventor) discloses an elastomeric insert supported by a bracket and affixed to the panel by reinforcing member. The insert is not removable from the panel.
U.S. Pat. No. 5,813,602 to Holland discloses an elastomeric insert affixed to the panel by an edge protector, an extension welded to the edge protector and a bolt inserted through the insert and extension secured by a nut (FIG. 5). The patent does not teach or suggest that the insert is intended to be removable without moving or removing the surrounding surface or panel. The position of the securing nut shows that it would be necessary to move the panel in order to access the bolts and the insert would have to be installed on the panel prior to placement of the panel. The position of the securing nut further shows that the panel would have to be moved in order to access the bolt and nut for removal of the insert.
U.S. Pat. No. 5,655,711 to Hull (the present inventor) discloses an elastomeric insert supported by a bracket and affixed to the panel an embedded reinforcing member.
U.S. Pat. No. 5,538,182 discloses an elastomeric insert affixed to the panel by a gripping member embedded in the insert and a cavity for receiving the gripping member where the insert is affixed to the panel by the frictional engagement of the gripping member and the cavity. Once engaged the insert cannot be removed from the panel.
U.S. Pat. No. 5,465,903 to Davis discloses an embedded system in which both field and gauge inserts are bolted to an anchor plate. The ""903 patent does not have a panel; rather, the entire system is made of elastomeric material both between the tracks and between the outside of the tracks and the roadway.
U.S. Pat. No. 4,415,120 to Thim discloses rubber inserts which are secured to the panels by screws. The ""120 patent does not teach removing the rubber inserts for any reason.
U.S. Pat. No. 4,236,670 discloses inserts secured to the panel by means of expanding bolts.
U.S. Pat. No. 2,950,057 to Speer discloses elastomeric inserts secured by a support plate and bolts welded to a plate, and a nut and washer affixed to the bolt after the elastomeric insert is positioned. The drawings indicate that once installed, only the bolts at the very ends of the system would be accessible, if at all. The ""057 patent does not teach or suggest that the insert would be removable without the need to move the panel to which the insert is attached. The xe2x80x9cUxe2x80x9d shaped design of the insert does not allow for access to the bolts once installed. Moreover, the ""057 patent teaches away from removability by stating xe2x80x9c[b]efore putting the rubber strip into place one side can be coated with a suitable rubber cement to provide an adhesive bond between the rubber strip 16 and plate 20xe2x80x3 (Col 3, 1. 15-18).
Therefore, the prior art does not disclose durable embedded railway track systems that reduce the flow of fluids and other foreign objects between the rail and the surrounding surface, that prevent a moveable surrounding surface from contacting or moving too close to the rails, that are removably attached to the surrounding surface, and that are easy to install, remove, reinstall and replace without moving or removing the surrounding surface.
The present invention which meets the needs identified above is an embedded railway system comprising one or more inserts removably affixed to a surrounding surface such as a concrete panel by one or more securement devices such as a bolt and a nut so that the inserts can be installed, removed, replaced or reinstalled without the need to move the surrounding surface.
The foregoing and other features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings wherein like reference numbers represent like parts of the invention.